A number of methods have been proposed for guiding the movement of a sliding panel with relation to a fixed panel, while at the same time providing means for braking that movement and fixing the position of the sliding panel. There remains a need, however, for mechanisms that simply, elegantly, and reliably combine these two functions. Preferably, such mechanisms also retain sufficient flexibility that they may be employed in a wide variety of contexts. The present invention fulfills these and other needs.